Medicine

METHODICAL INSTRUCTION FOR STUDENTS OF THE MEDICAL BIOLOGY, PARASITOLOGY AND GENETIC COURSE

METHODICAL INSTRUCTION FOR STUDENTS

ON MEDICAL BIOLOGY

Speciality “Nurse”

(distant form of studies)

 

LESSON № 4

 

Theme: Basics of Medical Parasitology. Medical Parasitology. Phylum Sarcomastigophora. Phylum Apicomplexa. Phylum Ciliophora.

 

Number of hours: 6

Aim: to know general characteristic of Protozoa, class Lobozea, morphological peculiarities, life cycles and pathogenic significance of Entamoeba histolytica, Entamoeba coli, Entamoeba gingivalis, Plasmodium, Toxoplasma gondii, Trichomonas, Lamblia intestinalis, Balantidium coli; be able to determine their reference to species, to ground the methods of laboratory diagnostics and prophylactics of amoebiasis, malaria, toxoplasmosis, trichomoniasis, lambliasis, and balantidiasis.

 

Professional orientation of students: Most species of Protozoa are pathogenic for man. Protozoa of class Sarcodina as Entaboeba histolytica are human parasites or commensals as Entamoeba coli and Entamoeba gingivalis. Malaria has been called the most important disease in the world today: probably over 300 million people presently have malaria, and one to two million people – mostly young children die of malaria each year.

Congenital toxoplasmosis is characterized by hydro- or microcephalus, chorioretinitis and cerebral calcification.

Cutaneus leishmaniasis, visceral leishmaniasis, African trypanosomiasis, American trypanosomiasis are tropical transmissible diseases. Trichomoniasis and lambliasis most common worldwide infections. Learning of the life cycle, clinical manifestation, main methods of laboratory diagnostic and the main principles of the prophylactics of amoebiasis, malaria, toxoplasmosis, leishmaniasis, trypanosomiasis, trichomoniasis and lambliasis is very necessary for practical medicine.

 

Methodology of Practical Class:(900 – 1200).

1. Entamoeba histolytica the causative agent of amebiasis

  Study the life-cycle of Entamoeba histolytica.

 

Draw large vegetative form (Forma magna). Mark at the drawing: ectoplasm, endoplasm, nucleus, pseudopodia, captured erythrocytes.


 

Large vegetative form (Forma magna):

1.

2.

3.

4.

5.


Task 2. Entamoeba coli – non-pathogenic commensal.

Draw cyst of Entamoeba coli. Mark 8 nuclei, cytoplasm and membrane at the drawing.


 

 

 

Cyst of Entamoeba coli:

1.

2.

3.

 


 

Task 3. Write the main characteristics of different species of Amoebae in the table.

Comparative chart of main characteristics of different species of Amoebae

Characteristics

Species of Amoebae

Entamoeba histolytica

Entamoeba coli

Localization inside human body

 

 

Nutrition

 

 

Cyst structure

 

 

Pathogenicity

 

 

Laboratory diagnosis

 

 

 

 

Task 4. Phylum Sarcomastigophora.Class Zoomastigophorea.

- Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense are the causative agent of African trypanosomiasis (sleeping sickness).

- Trypanosoma cruzi is the causative agent of American trypanosomiasis (Chagas’ Disease).

Draw some trypanosomes and erythrocytes. Mark at the drawing: cytoplasm, nucleus, blepharoplast, undulating membrane, flagellum.


 

Vegetative form of Trypanosoma:

1.

2.

3.

4.

5.


 

Task 5. Fill in a table “Comparison of species of trypanosomes”.

Characteristics

Trypanosoma brucei

Trypanosoma cruzi

Disease

 

 

Localization inside human body

 

 

Laboratory diagnosis

 

 

 

Task 6. Study the life-cycle of Trypanosoma brucei gambiense and Trypanosoma cruzi.


Life-cycle of Trypanosoma brucei gambiense

 

Pathogenicity ________________________

____________________________________

____________________________________

____________________________________

Route and factors of transmission _______

____________________________________

____________________________________

____________________________________

Agent of transmission _________________

____________________________________

 

Life-cycle of Trypanosoma cruzi

 

Pathogenicity ________________________

____________________________________

____________________________________

____________________________________

Route and factors of transmission _______

____________________________________

____________________________________

____________________________________

Agent of transmission _________________

____________________________________

 


Task 7. Leishmaniaes the causative agents of leishmaniasis

- Leishmania tropica - the causative agent of cutaneous leishmaniasis

- Leishmania donovani - causative agent of kala-azar, the black fever.

Examine under microscope (7 C 90) a slide of leishmania (stained with Romanowsky stain). Mark at the drawing: cytoplasm, nucleus, blepharoplast, flagellum.

 


Vegetative form of Leishmania:

1.

2.

3.

4.

 


 

Task 8. Fill in a table “Comparison of species of dermatotropic and viscerotropic Leishmania parasites”.

Characteristics

Leishmania tropica

Leishmania donovani

Source of invasion

 

 

Localization inside human body

 

 

Pathogenicity

 

 

Laboratory diagnosis

 

 


Life-cycle of Leishmania donovani

Life-cycle of Leishmania tropica major


 

Task 9. Trichomonas vaginalis the causative agent of urogenital trichomoniasis.

Draw trichomonas vaginalis. Mark at the drawing: nucleus, axostyle, flagellae and undulating membrane.


 

Vegetative form of Trichomonas vaginalis:

1.

2.

3.

4.


Pathogenicity _________________________________________________________________

_____________________________________________________________________________

Route and factors of transmission ________________________________________________

_____________________________________________________________________________

Laboratory diagnosis ___________________________________________________________

_____________________________________________________________________________

 

Task 10. Phylum Apicomplexa. Class Sporozoa.

Toxoplasma gondii the causative agent of toxoplasmosis.

Sketch endozoid of Toxoplasma gondii. Mark nucleus and cytoplasm.


Vegetative form of Toxoplasma gondii:

1.

2.


 

Give the characteristics of Toxoplasma gondii and study its life-cycle.

Pathogenicity _________________________________________________________________

_____________________________________________________________________________

Route and factors of transmission ________________________________________________

_____________________________________________________________________________

Laboratory diagnosis __________________________________________________________

_____________________________________________________________________________

 

 

Task 11. - Plasmodium vivax, the causative agent of tertian malaria.

- Plasmodium malariae, the causative agent of quartan malaria,

- Plasmodium falciparum, the causative agent of tropical (falciparum) malaria,

- Plasmodium ovale, the causative agent of tertian ovale-malaria.

Study the life-cycle of the malarial plasmodium. Mark the development stages of the parasite.

I – exoerythrocytic schizogony:

1- ___________________________________________________________________________

2 -___________________________________________________________________________

3 - ___________________________________________________________________________

4 -___________________________________________________________________________

II – endorythrocytic schizogony:

5- ___________________________________________________________________________

6 -___________________________________________________________________________

7 - ___________________________________________________________________________

8 -___________________________________________________________________________

III - Gametogony:

9- ___________________________________________________________________________

10 -__________________________________________________________________________

11 - __________________________________________________________________________

12 -__________________________________________________________________________

13- __________________________________________________________________________

14 -__________________________________________________________________________

15 - __________________________________________________________________________

 

Task 12. Mark the stages of development of Plasmodium vivax in human erythrocytes: 1- ring-form stage; 2 - mature trophozoite; 3 - mature schizont;  4 – macrogametocyte;  5 - microgametocyte.

         

    

 

Give the characteristics of Plasmodium vivax.

Source of invasion _____________________________________________________________

Invasive stage for a man ________________________________________________________

Localization inside human body __________________________________________________

_____________________________________________________________________________

Pathogenicity _________________________________________________________________

_____________________________________________________________________________

Laboratory diagnosis __________________________________________________________

_____________________________________________________________________________

Prevention ___________________________________________________________________

_____________________________________________________________________________

 

Task 13. Balantidium coli – the causative agent of balantidiasis.

Make following designations: macronucleus, micronucleus, cytostome, cilia, digestive vacuoles.

 


 

 

Vegetative form of Balantidium coli:

1.

2.

3.

4.

5.

6.

7.


 

Give the characteristics of Balantidium coli.

Invasive stage for a man ________________________________________________________

Localization inside human body __________________________________________________

Laboratory diagnosis ___________________________________________________________

_____________________________________________________________________________

Prevention ___________________________________________________________________

_____________________________________________________________________________

 

Seminar discussion of theoretical issues: (1230 - 1400).

Individual Students Program

You should prepare for the practical class using the existing textbooks and lectures. Special attention should be paid to the following:

1. Basics of Medical Parasitology. Medical Parasitology. Phylum Sarcomastigophora. Phylum Apicomplexa. Phylum Ciliophora.

1. The forms of association between organisms of different species.

2. Medical Parasitology as a science.

3. Classification of parasites and hosts.

4. Classification of Protozoa. General characteristic of Protozoa.

5.                 Species of class Lobozea: Entamoeba histolytica, Entamoeba coli, Entamoeba gingivalis.

8. General characteristic of class Zoomastigophorea.

9. Parasites of genus Trypanosoma: Trypanosoma brucei gambiense, Trypanosoma brucei rhodesiense, Trypanosoma cruzi.

10. Parasites of genus Leishmania: Leishmania tropica, Leishmania donovani.

11. Parasites of genus Trichomonas: Trichomonas vaginalis, trichomonas hominis.

2. Phylum Apicomplexa. Phylum Ciliophora.

1.                 General characteristic of phylum Apicomplexa.

2.                 General characteristic of class Sporozoa.

3.                 Malaria parasites of man: Plasmodium vivax, Plasmodium malaria, Plasmodium falciparum, Plasmodium ovale.

4. Toxoplasma gondii – the causative agent of toxoplasmosis

5. Balantidium coli – the causative agent of balantadiasis.

Test evaluation and situational tasks.

Multiple Choice.

Choose the correct answer / statement:

1. Which of these organisms is not classified as Protozoan?

A     Amoeba      B     Paramecium       C     Volvox           D     Plasmodium       E     Laminaria

 2. Which types of locomotive organelles does amoeba have?

A    cilia            B    pseudopodia        C    flagella        D    no locomotive organelles

3. What is the way of transmission of amebiasis?

A    sexual              B    alimentary               C    by blood

4. Which of these is mismatched?

             A     infective stage of amebiasis – mature cyst

             B     cyst of Entamoeba histolytica has 8 nuclei

             C     cyst of Entamoeba coli has 4 nuclei

             D     forma magna of Entamoeba histolytica – tissue form

             E      forma minuta of Entamoeba histolytica – commensal form

5. One patient was admitted to the hospital with a suggested diagnosis “amebiasis”. Which material should be taken for laboratory examination?

6. The feces of two patients with chronic inflammation of a colon were examined in the laboratory. 18 micro;m cysts with 8 nuclei were found in the faeces of the first patient and 10 micro;m cysts with 4 nuclei were found in the faeces of the second patient. Are the carriers of these cysts dangerous for other people? Explain your answer.

7. 4-nuclear cysts were revealed in faeces of healthy staff of a restaurant. Are the carriers of these cysts dangerous for other people? Explain your answer.

8. A foreign student (from India) came to the hospital. He complained of stomachache, frequent stool, containing mucus and blood. During laboratory analysis of faeces smear, vegetative form of amoeba (30-40 micro;m) were found. Which species and forms of amoeba were found in a patient? What diagnosis can be made?  

9. What type of host is man in the life cycle of Plasmodium malariae?

      A    Intermediate host             B    Definitive host             C    Reservoir host

10. What type of host is man in the life cycle of Toxoplasma gondii?

     A    Intermediate host              B    Definitive host             C    Reservoir host

11. One patient was admitted to the hospital with a suggested diagnosis “malaria”. Which material should be taken for laboratory examination?

    A   blood               B   urine              C   feces              D   material from breast bone puncture           E   material from lymph node puncture

12. Which organ can’t Toxoplasma gondii be found in?

A   blood              B   liver             C   lung             D   brain             E   lymph node

13. A child with multiple abnormalities of development was born. Examination of the family members has not found a hereditary pathology: karyotypes of the parents and the child are normal. What protozoan disease could cause such abnormalities of development?

14. A fever has developed in a patient two weeks after blood transfusion. What protozoan disease should be considered? What investigations must be performed to confirm  a diagnosis?

15. What are differences between Toxoplasma infection in an immunocompetent adult and a newborn?

16. What is “blackwater fever”? Which Plasmodium species causes it? Why?

17. Which types of locomotor organelles does lamblia have?

A   cilia          B   pseudopodia         C   flagella          D   no locomotor organelles

Correct answers of test evaluations and situational tasks:

1.C, E.  2.B.  3.B.  4.B, C. 5. Feces. 6.The carriers of these cysts are not dangerous for other people, because these cysts of E.coli.  7. The carriers of these cysts are dangerous for other people, because these cysts of E.histolytica.  8. E. histolitica, forma magna. Amebiasis.  9. A. 10. A. 11. A. 12. A.    13. Toxoplasmosis.    14. Malaria. Microscopy of patient’s blood smears stained with Romanowsky stain. 15. In immunocompetent adult toxoplasmosis mostly is asymptomatic. In newborns toxoplasmosis is characterized by hydro- or microcephalus, chorioretinitis and cerebral calcification when transplacental transmission of Toxoplasma gondii from an infected mother to the fetus occur.   16. The  “blackwater fever” is means the dark color of the urine of malaria patient. Plasmodium falciparum causes “blackwater fever”. P.falciparum causes occlusion of kidney capillaries with aggregates of parasitizes red cells. 17. B.

Self-study (1415 - 1500).

Written test students in “MOODLE”, thematic view instructional videos, in-depth study of material fact made in the independent work.

 

References 

Basic:

1. Bihunyak T.V. Medical Biology – Ternopil:TSMU, 2010. – 214 p.

2. Lynn B. Jorde Medical Genetics / Lynn B. Jorde, John C.Carey, Michael J.Bamshad [et al] – 2006. – 363 p.

3. Sylvia S. Mader Biology. / Sylvia S. Mader, Wm. C. Brown Publishers: Dubuque, Lowa – Melbourne, Australia – Oxford, England, IV edition. – 1996. – 850p.

4. Goodman R. Medical cell biology – Philadelphia, Lippincott-Reven, 1998. –

320 p.

5. Lazarev K.V. Medical biology – Simferopol: IAD CSMU, 2002. – 350 p.

6. Stephen L. Wolfe Introduction to Cell and Molecular Biology – Wadsworth Publishing Company, 1995. – 820 p.

7. G. Thomas Strickland Hunter’s Tropical Medicine – W.B. Saunders Company, 1984. – 1057 p.

Additional:

1. Alberts B. Molecular biology of the cell / Alberts B., Bray D., Lewis J. [et al] – Garland Publishing, NY&London, 1997. – 630 p.

2. Jan A. Pechenik Biology of the Invertebrates – Boston, Massachusetts, III-th edition, 1996. – 557 p.

3. Alberts B. Molecular biology of the cell / Alberts B., Bray D., Lewis J. [et al] –- Garland Publishing, NY&London, 1989. – 1218 p.

4. Strachan T. Human molecular genetics / Strachan T., Read A.P. – Bios Scientific Publ., 1996. – 596 p.

5. Sylvia S.Mader Biology. Art notebook / Sylvia S.Mader, Wm. C. Brown Publishers: Dubuque, Lowa – Melbourne, Australia, 1995. – 205 p.

6. USMLE STEP1. Biochemistry. Lecture notes. – 2004. – 351 p.

7. Elmer W. Koneman Color Atlas and Textbook of Dioagnostic Microbiology / Elmer W.Koneman, Stephen D.Allen, William M.Janda – Lippincott, 1997. – 1395p.

 

 

 

 

                                                                                                                             Methodical instruction

has been worked out by: Bihunyak Tatyana  

 

Methodical instruction was discussed and adopted

at the Department sitting 27.08.2013.

Minute № 1